Suffolk’s police chief says it’s impossible to pinpoint one cause of a 14.2-percent drop in crime in Suffolk last year, because there are many factors that affect crime rates.

“To pinpoint one, or even three or four, it’s very difficult,” Chief Thomas Bennett said.

But he has a few ideas on what caused the decrease, and they include cooperation with citizens, hard-working officers and an economy that seems to be strengthening.

Decreases in burglaries and larcenies, the most-reported crimes in Suffolk, especially drove the overall decline, Bennett said.

“In this city, larceny and burglaries drive the crime numbers,” he said, noting burglaries fell by a third and larcenies were down 8.4 percent. “That’s very significant, because we have a lot of those reports. That’s what really drove the overall decline.”

But most other serious crime categories saw decreases, too. Homicide fell 71.4 percent. Robbery was down 18.8 percent, and aggravated assault was down 17.4 percent.

The number of vehicle thefts reported was down 17.2 percent, and arson was down a whopping 59.1 percent.

The only “Part I” crime — a Federal Bureau of Investigation classification — that saw a slight increase was rape, up 5.9 percent.

Discussing likely factors in the declines, Bennett mentioned first a good working relationship with the city’s residents.

“We get a lot of information from our citizens, and that’s helpful, because a lot of times, without that, we can’t solve cases,” he said.

“I think our officers are working harder than they’ve ever worked,” Bennett continued about his department.

He also speculated the economy, which he characterized as “not as bad as it was,” could be helping.

Furthermore, he said, “Getting the right people off the street and in jail helps crime numbers a lot sometimes,” he said. “A large percentage of crime is committed by just a few people.”

He thanked the work of the Commonwealth’s Attorney’s office for helping get the right people in jail, and also cited support of City Council and city administration in making public safety a priority.

“It takes a lot of people, and not just the police department, working together to get crime numbers down,” he said.

The city’s two homicides in 2014 were a sharp drop from the seven in 2013, but a suspect has yet to be identified in one of them.

Within hours of the crime, three people were arrested in the Sept. 22 slaying of 82-year-old downtown businessman Donald Carter. The suspects — Leon Jerome Hayes, Naomi Nichelle Lambert and Katron Shawndell Walker — were indicted in December, and their cases currently are going through the legal system.

But police haven’t had such success tracking down the responsible parties for the death of Virginia Mae Hill on Oct. 18.

“We’re still working it,” Bennett said of the investigation. “We’re still hoping someone will come forward and give us that little bit of information. We feel like we’re one or two pieces away.”